condition mean min max ZT0-3 6.2614125000000005 5.64994 6.872885 ZT4-7 20.657899999999998 20.657899999999998 20.657899999999998 ZT8-11 27.2472 27.2472 27.2472 ZT12-15 0 0 0 ZT16-19 22.47325 22.47325 22.47325 ZT20-23 14.04865 14.04865 14.04865